Reinforced elongate metal body

ABSTRACT

The invention relates to an elongate metal body, for instance an aluminium rod with a chosen cross-sectional form manufactured by extrusion. It is a first object of the invention to make an elongate metal body stiffer and stronger without this entailing an increase in weight. In respect of this objective the metal body according to the invention has the feature that the body has at least one cavity extending at least to a considerable degree in longitudinal direction, in which cavity is received a pre-manufactured elongate reinforcing rod, of which at least the ends are coupled to the body in force-transmitting manner.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention relates to an elongate metal body, for instance analuminium rod with a chosen cross-sectional form manufactured byextrusion.

2. Background Information

Such a body is known in many applications. A well-known application is askate frame for an ice-skate or roller-skate. Such a frame comprises forinstance an elongate carrier manufactured from aluminium by means ofextrusion, to which the runner or wheels are connected.

SUMMARY OF THE INVENTION

It is a first object of the invention to make an elongate metal bodystiffer and stronger without this entailing an increase in weight. Inrespect of this objective the metal body according to the invention hasthe feature that the body has at least one cavity extending at least toa considerable degree in longitudinal direction, in which cavity isreceived a pre-manufactured elongate reinforcing rod, of which at leastthe ends are coupled to the body in force-transmitting manner.

The embodiment is recommended in which the rod consists substantially ofa bundle of longitudinally extending, continuous fibres embedded in aplastic matrix, in particular consisting of carbon, aramid, glass,boron, reinforced polyethylene and other synthetic and ceramicmaterials. Such a rod of composite material combines a very greatlongitudinal strength with a low weight.

A very simple and inexpensive embodiment is that in which the rod isconnected to the body by glue.

For strengthening and reinforcement this variant can have the specialfeature that the rod is connected substantially along its whole outersurface to the body.

A further variant is characterized by biasing means for holding the rodunder longitudinal bias.

For particular applications this variant can have the special featurethat the biasing means are adjustable.

A specific embodiment hereof has the feature that the biasing meanscomprise screw means.

The biasing means can be embodied such that the rod fits into the cavitywith small clearance and the biasing means are adapted to exert apressure force on the ends of the rod.

An embodiment with optionally adjustable biasing means can have thespecial feature that the cavity is positioned at a distance from theneutral fibre of the body. The metal body comes under strain of bendingdue to the longitudinal force exerted at a distance from the neutralfibre. A bending can thus be obtained which, in the case of adjustablebiasing means, can be adjusted to a desired value.

This latter embodiment in particular can, as will be describedhereinbelow, be important for application in the skating sport. This isthe case however for the invention in general. The invention thereforealso pertains to a skate frame for an ice-skate or roller-skate which isprovided with an elongate metal body having connected thereto anelongate reinforcing rod as specified above.

A runner for an ice-skate is generally ground with a determined radiusof curvature. This radius of curvature is arranged in the heightdirection of the skate.

In the case of short-track skating and 500 metre sprint skating on thetrack it is at the moment usual for the skates also to have a certaincurvature in sideways direction. The value thereof, which can beexpressed in the radius of curvature, is greatly dependent on personalwishes and preferences. At the moment the skate frame is herein usuallyclamped in a vice, wherein a part of the skate is bent manually. Theobject of this bending operation is to obtain a better grip on the icein the bend, whereby the skater can negotiate the bend at an evengreater angle and speed without the risk of slipping.

As has been stated, the value of the radius of curvature to be adjustedis very person-dependent. The degree of bending must moreover be adaptedto the ice conditions, so that there is a need for an adjustablebending.

For the purpose of grinding the runner it is further desirable that theskate is straight or can be straightened when not in use, so that therunner can be clamped into usual grinding devices. It is thereforedesirable that the runner can be straightened again with simple means.

The above described steps according to the invention, for instancebiasing means adjustable by means of screw means, obviate the abovedescribed problem.

Due to the combination of materials with different coefficients ofexpansion there occurs a difference in expansion or shrink of thematerials in the case of temperature changes. For instance in thecombination of an aluminium frame in which a steel runner is arranged,the following phenomenon occurs. A radius in the runner of for instance20 metres at room temperature will have a radius of curvature at minus15° C. of about 17 metres. This temperature-dependent radius ofcurvature is undesirable if it does not correspond to the radius ofcurvature desired at these temperatures. There therefore exists a needto change the effective coefficient of expansion, locally or otherwise,of an aluminium skate frame in order to thus make it possible tocompensate for the deformation due to temperature differences.

The stiffness of a skate frame is also of great importance. Due to thegreat forces during starting, sprinting and taking of a bend, the skateand the frame have a tendency to deform. This deformation must belimited to a minimum. If a skate is subjected to bending, a small radiusof curvature must be arranged in advance both in height and in sidewaysdirection in order to still have the correct radius of curvature in thebend. This has the disagreeable consequence that the straight part ofthe skate track must be skated with a small radius of curvature, whichadversely affects the speed. For these reasons there therefore exists aneed for a stiff skate frame.

This need for more stiffness and strength also exists in otherconstructions, such as for instance in aluminium boat masts, booms andthe like. Other applications relate to ladders, for instance fireladders, aluminium profiles in the building industry, glasshouseconstruction etc. Supporting aluminium profiles also often have thelimitation of insufficient stiffness and strength. The inventionprovides a solution herefor.

It is noted that particularly the biasing means according to theinvention can cause a bending in two directions. For this purpose twopush or pull rods are then connected to the profile, this at mutuallydiffering positions relative to the neutral fibre, for instance suchthat the one rod causes a sideward bending and the other rod a bendingin vertical direction.

By arranging carbon rods in the outer wall of a skate frame thestiffness is improved to a significant extent. Carbon fibres have astiffness which is a factor 3-6 times higher than that of aluminium,while the specific mass amounts to about half thereof. The strength ofcarbon is 4-10 times that of aluminium. The structure of the elongatemetal body can thus be lighter while retaining strength and stiffness.

Another advantage of carbon fibres is that these fibres display a fullyelastic behaviour. This in contrast to for instance the aluminium, wherethe elasticity limit is relatively low and a permanent plasticdeformation occurs quite rapidly when there is load. The stiff andstrong carbon fibres prevent this plastic deformation of the aluminium.

The reinforcing rod which according to the invention is added to theelongate metal body has in the most general sense better properties thanthe material of the metal body itself, particularly in respect ofstrength and stiffness. The gluing of the rod into the cavity takesplace for instance with an epoxy glue. Aluminium bodies are preferablyanodized with usual methods to thus obtain a suitable gluing surface.Other cleaning and surface treatments, such as for instancechrome-plating, can be used.

A reinforcing rod can have a desired cross-sectional form, for instancea round form or can have another cross section adapted to the geometryof the cavity or the metal body, for instance square, rectangular,polygonal.

The cavity can for instance be arranged completely internally in thebody. A cavity can also be partially open to the outside in longitudinaldirection, which simplifies the extrusion process for manufacturing themetal body. The opening of such semi-open forms can be situated on theinside or the outside of the profile. In this latter case thereinforcing rod is partly visible on the outside.

In the case of an enclosed cavity in a metal body a reinforcing rod,which is for instance obtained via a pulltrusion process, is pushed intothe cavity. The glue can herein be pre-applied to the rod and/or in thecavity.

Another method is to insert the rod into the cavity without glue. Bysupplying glue to the one open side and sucking on the other side of thecavity (in which the rod is received), the glue can be applied betweenthe wall of the cavity and the reinforcing rod so that it wholly fillsthe remaining space.

BRIEF DESCRIPTION OF THE DRAWINGS

Further characteristics and special features of the invention will nowbe elucidated with reference to the annexed drawings. Herein:

FIG. 1 is a schematic perspective view of a skate with a frame accordingto the invention;

FIG. 2 shows the cross section II--II according to FIG. 1 on enlargedscale;

FIGS. 3, 4, 5 and 6 show cross sections through alternative profiledrods embodied as skate frames;

FIG. 7 is a partly broken away perspective view of a skate frame anddevice for gluing in a reinforcing rod;

FIGS. 8 and 9 show cross sections through other examples of extrusionprofiles with a plurality of reinforcing rods in accordance with theteaching of the invention;

FIG. 10 shows a cross section through two coacting profiles formanufacturing a body according to the invention;

FIG. 11 shows a cross section through a variant;

FIG. 12 is a partial side view of a drive shaft according to theinvention with torsion- and bending-stiffness;

FIG. 13 is a schematic perspective view of an interrupted profile withcontinuous reinforcing rods;

FIG. 14 is a schematic perspective partial view of a variant;

FIG. 15 shows a longitudinal cross sectional view of the embodimentaccording to FIG. 14 during production;

FIG. 16 shows a cross section through yet another embodiment;

FIG. 17 shows a schematic longitudinal section through a variant;

FIG. 18 shows a cross section through another variant;

FIG. 19a shows a cross section through a reinforcing profile;

FIG. 19b shows a section through an aluminium tube for reinforcing;

FIG. 19c shows the assembly of the parts according to FIGS. 19a and 19bwith reinforcing rods;

FIG. 20a shows a reinforcing body according to the invention;

FIG. 20b shows a beam reinforced therewith;

FIG. 21a shows an alternative reinforcing body;

FIG. 21b shows an alternative beam reinforced therewith;

FIG. 22 shows a reinforced beam in cross section;

FIG. 23 shows an alternative reinforced beam in cross section;

FIG. 24 shows yet another beam in cross section;

FIG. 25 shows a reinforced tube in cross section;

FIG. 26 is a schematic view of a device for manufacturing a fixedlybiased structure according to the invention;

FIG. 27 is a schematic view through a set of windmill blades;

FIG. 28 is a schematic view of a beam to be placed-under strain ofthree-point bending;

FIG. 29 is a schematic view of a vertical pole clamped on its undersideand to be placed under strain of bending along its length;

FIG. 30 shows an example of a composite body with reinforcing rodsaccording to the invention; and

FIG. 31 shows a graphic representation of tension curves of determinedcarbon fibres and aluminium extrusion material for the purpose ofelucidating an important application of the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIG. 1 shows an ice-skate 1. This comprises a shoe 2, a sole support 3connected to the sole thereof and a heel support 4 connected to theheel. Connected to these supports 3 and 4 is an extruded aluminiumprofile 5, on the underside of which a runner 7 is glued into a groove6. The profile 5 shows a downward tapering form and is provided with twocavities respectively 8 and 9 extending in longitudinal direction. Therelatively large cavity 8 has the function of reducing the weight ofprofile 5. The cavity 9 has a cylindrical form in this embodiment.Arranged with small clearance in this cavity 9 is a reinforcing rodconsisting of a bundle of continuous carbon fibres extending inlongitudinal direction and embedded in a plastic matrix. At both ends ofcavity 9 a screw thread is tapped in the wall thereof, into which areplaced screws 11, 12 which are operable from outside by means of a tool10. The screws engage for pressing on the carbon rod 13 in the mannershown in FIG. 2. By rotating the tool 10 as according to arrow 14 thepressure force exerted on rod 13 is increased, whereby as a result ofthe relatively great pressure strength of this rod 13 relative to thealuminium of the profile 5 this latter is subjected to a bending whichis indicated with the dash-dot line 15. The profile and the runner 7hereby acquire a bent form, the radius of curvature of which isadjustable.

FIGS. 3, 4, 5 and 6 show respectively frames 16, 17, 18, 19 in which thereinforcing rods 13 are arranged. Frames 17, 18, 19 have additionalreinforcing rods 20, 21, 22 respectively.

For instance the embodiment according to FIG. 4 offers the possibilityof influencing the curvature in the horizontal plane as well as that inthe vertical plane. The rod 13 can influence the horizontal curvature inthe same manner as described with reference to FIGS. 1 and 2, while therod 20 influences the curvature in the vertical plane. This embodimentis such that the neutral fibre 23 of the structure is situated at thepoint of intersection of the vertical plane 24 through rod 20 and thehorizontal plane 25 through rod 13. Hereby the bendings caused by rods13 and 20 are substantially independent of one another.

The structure according to FIG. 5 comprises two cavities accessible viaopenings 26, in which cavities the rods 13 and 21 are situated. Duringmanufacture the frame 18 can be turned over temporarily in order to pourglue into the cavities for the purpose of gluing rods 13, 21 therein.

Attention is drawn to the fact that the cavity 9 according to FIG. 1 isplaced at a distance from the neutral fibre of the profile 5. Rod 13 canthereby only be bent in an inclining plane, which assumes a positionbetween the planes 24 and 25 drawn in FIG. 4.

FIG. 7 shows a profile 27 which bears a strong resemblance to theprofile 18 according to FIG. 5, but differs therefrom in that thecavities 28 are separate from the central cavity 29. In this embodimenta carbon rod 13 is first arranged in a cavity 28, a glue reservoir 31 issubsequently connected via a conduit 30 for supplying glue into cavity28, into which rod 13 is placed beforehand. Glue is subsequently drawnin by means of a suction pump 32, which is connected to the other end ofcavity 28 by means of a conduit 33, such that the glue fills theinterspace between the wall of cavity 28 and the rod 13. The glue isoptionally cured by an increase in temperature. If desired, the openends of cavities 28 can be covered with a plug.

FIGS. 8 and 9 show cross sections through respective profiles 34 and 35.Profile 34 can for instance serve as sailing boat mast. Reinforcing rodsare designated with reference numeral 36.

The profile 35 is an I-beam which is intended as construction elementfor building structures. These profiles 34, 35 can also be manufacturedby extrusion from aluminium.

FIG. 10 shows two partially depicted profiles 41, 42 which can be movedtoward one another as according to arrow 43 such that protrusions 44 ofprofile 42 are inserted into spaces 45 of profile 41 such thatcylindrical channels result. Reinforcing rods are placed beforehand inthe spaces 45. With suitable means, for instance glue, the profiles 41,42 are held together such that the reinforcing rods (not shown) areconnected to the obtained structure in force-transmitting manner.

FIG. 11 shows a variant in which an elongate body 46 has undercutrecesses 47 in which reinforcing rods 48 are prearranged. The recesses47 are subsequently covered by a plate 49. The profiles according toFIGS. 10 and 11 can be manufactured very suitably by means ofpulltrusion. It is important to prevent corrosion between the carbon rodand the material of the relevant profile, in particular aluminium. Acomplete embedding and sealing relative to the environment can serve forthis purpose.

FIG. 12 shows a drive shaft 50 with a very slightly helical form. Thishelical form is obtained after extrusion of shaft 50 by for instanceapplying a heavy torsional stress to the initially straight-extruded,tubular drive shaft, whereby a plastic deformation occurs. The driveshaft provided beforehand with reinforcing rods 51, 52 thus obtains inthis embodiment a greatly increased one-sided torsion stiffness. Atwo-sided increase in the torsion stiffness can also be envisaged byarranging reinforcing rods running crosswise. The described manner ofmanufacture cannot be applied here.

It can be of importance to use a glue for gluing in reinforcing rodswhich has a high resistance to creep stresses at an increasedtemperature. An increased resistance can be obtained by addingtemperature resistant particles to the glue. These may be metal orceramic particles. A glue with a high glass transition temperature alsoprovides an increased resistance of the glue connection to creep. It isnoted that creep or relaxation occurs in glues and matrix materials inthe case of prolonged load at increased temperature.

An epoxy glue can be provided with so-called flexibilizers, wherebyshock and peak loads can be absorbed better. In the case of an epoxyglue for instance an increased flexibility is obtained by addingslightly more hardener relative to the resin part than is prescribed fornormal applications. The addition of fine rubber particles is also veryeffective in relation to the desired flexibility.

When reinforcing rods of glass fibre are used, these glass fibres canalso serve for data transmission.

Glass can be cast into cavities in extrusion profiles as reinforcingmaterial. In this manner a very good vacuum or pressure through-feed canalso be realized.

Profiles can be applied wherein at least a number of cavities extendingin longitudinal direction are used for other purposes, for instance datatransport, liquid transport or gas transport.

Additional channels can if desired also be used for bringing a profileto and holding thereof at a determined temperature. Particularly insituations where excessively high temperatures can adversely affect thequality of the construction, cooling of an aluminium profile can berealized by causing coolant to flow through the relevant channels.

The internal surface of the longitudinally extending cavity can bepretreated to improve adhesion of an applied glue. The surface can forinstance be treated with a solution of sodium hydroxide, potassiumhydroxide or the like. These agents dissolve a small portion of thesurface, thereby removing the oxide skin which is disadvantageous inobtaining a good adhesion. After pickling with such a caustic soda thesurface is washed well with water and then dried. Gluing must take placerelatively quickly after this pickling process in order to preventrenewed oxide formation. After the pickling the surface can also bepassivated in the usual manner by for instance chrome-plating oranodizing.

By pickling the inner surface of the cavities with caustic soda theinner diameter of the cavity can also be increased. The enlargementobtained is dependent on the duration, concentration and temperature ofthe caustic soda. The glue gap (see FIG. 7) between the wall of thecavity and the reinforcing rod requires a value with close tolerance.The extrusion process for manufacturing an extruded aluminium profilecannot be performed well in respect of this close tolerance. The cavitycan be widened in the described manner by pickling. When the cavitieshave mutually differing diameters, different pickling times can beprescribed per cavity in order to eventually obtain the nominal diametereverywhere.

FIG. 13 shows an interrupted profile consisting of blocks 53 throughwhich three carbon reinforcing rods 54 extend continuously. In thisembodiment blocks 53 can provide the desired positioning of the carbonrods 54 and can be used to discharge the forces to the environment. Theapplication of the structure shown in FIG. 13 is for instancereinforcing existing structures under strain of bending, such as bridgesand other frames, for instance the heavily loaded frames of transportmeans such as trucks.

FIG. 14 shows a beam 55 in which three carbon rods 56 extend inlongitudinal direction. Zones 57 pressed plastically inward are arrangedfrom outside to fix the carbon rods 56.

FIG. 15 shows the manner in which these plastic deformations can bearranged. The beam 55 is carried through the pinch between anon-profiled lower roller 58 and a profiled upper roller 59. The form ofthe profiling of roller 59 is transferred to the beam 55 in the form ofthe depressions 57.

FIG. 16 shows a variant in which a reinforcing rod 60 is pressed fromoutside by a screw 61.

FIG. 17 shows a variant in which the outer end of a carbon rod 62 isglued and clamped fixedly by means of a wedge 63. The elongate body 64has for this purpose a channel 65 with a form widening toward theoutside.

FIG. 18 shows a floor part 66 which is embodied as aluminium extrusionpart and comprises a flat upper plate 67 which is reinforced on itsunderside by ribs 68 which are reinforced on their bottom part withcarbon rods 69. The plates 67 can be mutually coupled by means ofundercut longitudinal recesses 70 and correspondingly formedlongitudinal protrusions 71.

FIG. 19a shows a cross-shaped extruded aluminium profile 72 withcavities 73 for receiving reinforcing rods.

FIG. 19b shows an aluminium tube 74.

FIG. 19c shows the assembly of the reinforcing cross 72 and thealuminium tube 74, wherein carbon rods 75 are arranged in cavity 73 bymeans of glue. A unitary reinforced structure is hereby obtained.

FIG. 20a shows a reinforcing bar 76 into which carbon reinforcing rods77 are glued. FIG. 20b shows that a beam 78 is reinforced with two suchbars 76 which are connected thereto by screw means 178.

FIG. 21a shows an alternative reinforcing bar 79, which can be insertedin longitudinal direction in the manner shown in FIG. 21b in order toreinforce beam 80.

FIG. 22 shows a beam 81 which is reinforced with carbon reinforcing rods77.

FIG. 23 shows an alternative, wherein a beam 82 is assembled from twoequal parts 83. The flanges 841 are mutually connected by for instancebolts (not shown).

FIG. 24 shows a part of a beam 83 in accordance with the teaching ofFIG. 11.

FIG. 25 shows a tube 184 reinforced with carbon rods 77. Due to theshown orientation and structure a very strong and light cycle frame canfor instance be constructed with a high bending stiffness, in particularin the x and y direction.

FIG. 26 shows schematically the manner in which a very light and veryelongate structure with bending stiffness can be manufactured. Betweentwo flanges 85, 86 a number of tubes 186 are positioned inpressure-resistant manner. Carbon rods 87 extend in these aluminiumtubes. Non-cured epoxy glue is present in the space between the innerwall of a tube and the carbon rod. The flanges 85, 86 are urged towardone another by the shown screw construction, whereby a pressure stresswith associated shortening results in tubes 186. The carbon rod 87 isarranged freely in the inner space and therefore not subjected to thispressure force and associated shortening. Curing of the epoxy glue issubsequently carried out, optionally with a certain increase intemperature. Due to the relaxation there now results a biasedconstruction whereby a pressure force is maintained in the aluminiumtube in combination with a corresponding tensile force in the carbonrod. Heating can take place as desired by hot air, hot water orelectrical heating, for instance by passing an electric current throughthe carbon rods. An electric current can also be passed through thealuminium profile.

FIG. 27 shows two windmill blades 88, 89 which are placed at a mutualdistance but which are mutually connected by means of continuous carbonrods 90, which also extend in the middle zone. A central block 91 servesfor coupling to the blade shaft 92. The block 91 is provided withcontinuous holes 93 for passage of carbon rods 90.

The blades can for instance consist of aluminium or plastic.

The blades 88, 89 may also consist of mutually coupled parts. What isimportant is that the carbon reinforcing rods hold together the totalstructure and provide the necessary tensile strength.

FIG. 29 shows a pole 95 which is clamped on its underside 94 and whichcan be placed under strain of bending by means of forces designatedsymbolically with an arrow 96. What can be envisaged here is forinstance a mast, for instance a flagpole, a ships mast, a lamppost orthe like. Glued-in carbon reinforcing rods of different length are drawnsymbolically. These rods 97, 98, 99 respectively provide a reinforcementsuch that the effective cross-sectional surface of the collective rodsalong the length of pole 95 varies by and large in accordance with thereinforcement desired at each axial position.

FIG. 28 shows a beam 100 based on the same mechanical principle. Thebeam 100 supported on its ends is loaded in the middle with a bendingforce 101. Due to this three-point load the bending moment is zero atthe ends of the beam and maximum in the middle. In accordance herewithfour reinforcing rods are drawn symbolically, designated respectivelyfrom long to short with 102, 103, 104 and 105.

FIG. 30 shows the coupling of profiles 106, 107 placed at a mutualangle. The outer surfaces extending transversely of the connecting seam108 have a rounded and recessed form and are thus made suitable forgluing in of carbon reinforcing rods.

FIG. 31 shows a graphic representation of four different carbon fibresof the Toray brand and also of an aluminium extrusion material (AlMgSi1; 6061).

This graphic representation shows that in particular carbon fibrematerial of the type T800 from the manufacturer Toray combines a veryhigh limit of elasticity of 1.9% with a very high tensile strength, i.e.5586 Mpa. The modulus of elasticity of this fibre material amounts to294 Gpa.

The three other fibre types T300, M40J and M46J also have the samefavourable properties, albeit to a slightly lesser degree. Theapplication of such fibres as reinforcing rods of the type according tothe invention in the automobile manufacturing industry is very suitablein view of the ever increasing demands being made in respect of crashconsequences. It is important in crashes that the bodywork remainsintact but nevertheless provides the possibility of withstanding thegreat forces which occur by means of plastic deformations (crush zones).

In normal use a profile reinforced with carbon can already give aconsiderable weight-saving with improved properties. The aluminium mayabsorb without any problem as much stretch as is required for thestretch of the reinforcing fibres to utilize the full strength of thefibre material. Full benefit can hereby be derived from the strength andthe stretch possibilities of the carbon material. Reference is made inthis respect to the graph of FIG. 31.

It is noted that the above mentioned manufacturer Toray also supplieseven stronger carbon fibres, for instance of the type T1000. Fibres witha considerably lesser stiffness can also be used, such as the abovementioned glass fibres, aramid fibres or polyethylene fibres. Thedesigner of such structures must then realize that higher demands arethen made of the stretch possibilities of the aluminium.

The coefficient of expansion of carbon fibre material is smaller thanthat of aluminium. The coefficient of expansion of the plastic matrix ishowever considerably larger than that of aluminium. By now choosing asuitable ratio of the quantity of carbon fibres and the plastic matrixmaterial, a coefficient of expansion can be obtained which is equivalentto that of aluminium. Due to this equivalence of the coefficient ofexpansion the glue is variably loaded in radial direction either not atall or to a negligible degree in the case of temperature fluctuations,which will result in a longer lifespan.

Other very strong materials can also be glued in, such as specialaluminium and/or lithium alloys. Such materials are often difficult toextrude in complicated forms and the strength can often be increased byfor instance cold deformation. Known in this respect is the so-calledcold-drawn wire. Benefit can here also be derived from the equalcoefficients of expansion.

What is claimed is:
 1. An article of manufacture, comprising:an elongatemetal body of a chosen cross-sectional form, the body having at leastone cavity of a chosen cross-sectional geometry extending substantiallyin a longitudinal direction; and a pre-manufactured elongate reinforcingrod having a bundle of longitudinally-extending, continuous fibersembedded in a plastic matrix, wherein the reinforcing rod is received inthe at least one cavity connected to the body in a force transmittingmanner and completely embedded and sealed in the at least one cavity. 2.The article of claim 1, wherein the reinforcing rod is connected to thebody by glue.
 3. The article of claim 2, wherein the glue has particlesadded thereto.
 4. The article of claim 3, wherein the particles aretemperature resistant.
 5. The article of claim 3, wherein the particlesare one of metal and ceramic.
 6. The article of claim 3, wherein theparticles are rubber particles.
 7. The article of claim 2, wherein theglue is an epoxy glue.
 8. The article of claim 2, wherein the glue hasincreased resistance to creep stresses at increased temperature.
 9. Thearticle of claim 2, wherein at least a portion of the cavity surface istreated to improve adhesion of the glue.
 10. The article of claim 9,wherein the cavity surface is treated by one of pickling, passivating,etching, chromatizing, chrome-plating, anodizing, de-greasing and makingoxide-free.
 11. The article of claim 1, wherein at least one end of thereinforcing rod protrudes beyond the body.
 12. The article of claim 1,wherein a further body is coupled to the body by the reinforcing rodextending through both the bodies.
 13. The article of claim 11, whereinthe body is an extruded aluminum beam.
 14. The article of claim 1,wherein the reinforcing rod has a cross-sectional form configured tocooperate with the geometry of the cavity.
 15. The article of claim 14,wherein the cross-sectional form of the reinforcing rod is circular. 16.The article of claim 1, wherein the reinforcing rod is connected to thebody substantially along its entire outer surface.
 17. The article ofclaim 1, wherein the at least one cavity in the body is formed betweencomplementary components forming the body.
 18. The article of claim 1,wherein the at least one cavity is partially open to the outside so asto form an open sided recess in which the reinforcing rod is positioned.19. The article of claim 18, wherein the open sided recess is covered bya plate coextending with the body.
 20. The article of claim 1, whereinthe reinforcing rod fits into the cavity with a small clearance.
 21. Thearticle of claim 1, further including biasing means for holding thereinforcing rod under longitudinal bias.
 22. The article of claim 21,wherein the longitudinal bias is adjustable.
 23. The article of claim22, wherein the biasing means includes screw means.
 24. The article ofclaim 21, wherein the biasing means is adapted to exert a pressure forceon the ends of the reinforcing rods.
 25. The article of claim 21,wherein the cavity is positioned at a distance from a neutral fiber ofthe body.
 26. The article of claim 1, wherein the body is formed as askate frame for one of an ice skate and a roller skate.
 27. The articleof claim 26, wherein the skate frame has a longitudinal curvature. 28.The article of claim 27, wherein the longitudinal curvature isadjustable.
 29. The article of claim 1, wherein the reinforcing rod isreceived in the at least one cavity under fixed bias.
 30. The article ofclaim 1, wherein the reinforcing rod is made of metal.
 31. The articleof claim 30, wherein the metal is selected from the group consisting ofsteel, aluminum, lithium and aluminum alloy.
 32. The article of claim 1,wherein the continuous fibers include carbon fibers.
 33. The article ofclaim 32, wherein the carbon fibers have an elasticity limit of morethan 1%, a tensile strength of more than 3 Gpa and an elasticity modulusof more than 180 Gpa.
 34. The article of claim 33, wherein the carbonfibers are of the T800 type.
 35. The article of claim 32, wherein aquantity of the carbon fibers and the plastic matrix is chosen in aratio such that a coefficient of expansion is obtained which issubstantially equivalent to that of the body.
 36. The article of claim1, wherein an effective cross-sectional surface of all of a plurality ofreinforcing rods collectively along a length of the body varies inaccordance with a locally desired reinforcement.
 37. A method of formingan article of manufacture, comprising the steps of:extruding an elongatemetal body of a chosen cross-sectional form, the body having at leastone cavity of a chosen cross-sectional geometry extending substantiallyin a longitudinal direction; positioning an elongate reinforcing rod inthe at least one cavity by co-transport with the extruded body; anddrawing in glue to the cavity by a suction pump connected to an end ofthe cavity, wherein the reinforcing rod is connected to the body in aforce transmitting manner and is completely embedded and sealed in theat least one cavity.
 38. The method of claim 37, further including thestep of allowing the glue to harden with the body in a pressedcondition.
 39. The method of claim 37, further including the step ofallowing the glue to harden with the reinforcing rod in a tensionedcondition.
 40. The method of claim 37, further including the step ofcuring the glue at an increased temperature.
 41. The method of claim 40,wherein the temperature is increased and the glue is cured by the stepof passing an electric current through the reinforcing rod.
 42. Anarticle of manufacture, comprising:an elongate metal body of a chosencross-sectional form, the body having at least one cavity of a chosencross-sectional geometry extending substantially in a longitudinaldirection; and a pre-manufactured elongate reinforcing rod having abundle of longitudinally-extending, continuous fibers embedded in aplastic matrix received in the at least one cavity, wherein thereinforcing rod is connected to the body in a force transmitting manner,and the rod is connected to the body substantially along its entireouter surface.